


A Mailbox Never Lies (BillDip)

by CatNip_618



Series: Gravity Falls [2]
Category: Gravity Falls
Genre: 4 years after Weirdmageddon, 4th wall breaking mailboxes, BillDip, Billdip fluff, F/F, Fluff, Gayness, M/M, MxM - Freeform, The Mailbox, dippers guide to the unexplained, older! Mystery Twins, revealing secrets
Language: English
Status: Completed
Published: 2018-12-16
Updated: 2018-12-16
Packaged: 2019-09-19 21:19:31
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,582
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17009409
Author URL: https://archiveofourown.org/users/CatNip_618/pseuds/CatNip_618
Summary: 23-year-old Dipper and Mabel Pines find the mailbox that was recorded in 12-year-old Dipper’s “Guide to the Unexplained — the Mailbox”.After Mabel slips in a question referencing her twin brother, secrets neither twin knew are brought to life and their trip ends with an unexpected visitor.





	A Mailbox Never Lies (BillDip)

Mabel’s short hair tickled her cheeks as the gentle breeze caused to it sway slightly. Her twin brother, Dipper, shouldered his backpack a little, mumbling something about the atmosphere being too awkward. 

The Mystery Twins had grown healthily and reached staggering heights. The male was 6’2 while the female was 5’9, granted their elderly parents’ youthful tallness. Mabel had cut her hair about a year ago, and had been keeping it that way. Dipper, on the other hand, didn’t really change except he got more manly. 

It was kind of a distant wish-come-true for the young man (finally being manly), in his opinion.

The twins had already graduated university, even at the age of 23, and both earned bachelors (and some masters) in forensics science. Even with their opposites and unequal personalities, they still had the brains and smarts. 

“Hey, Dipstick,” Mabel started, “remember that talking mailbox?” 

Dipper stumbled out of his trance. “Huh? Oh yeah, I remember...” Mabel sighed, her aura nostalgic. Lots of things had happened before Weirdmageddon, but afterwards? It was still teeming with barf fairies, undersea island heads, and the so-called “Steve” who ate their Grunkle’s car more than forty odd years ago. 

“It was cool when it—Hey! What a coincidence!” The female brunette stopped in her tracks, startling the male brunette. “Whoa! Hey, what’s with the traffic?” Mabel shushed him, not sure of what she was looking at. 

Dipper followed her gaze as his eyes widened. “Is that...?” 

Mabel grinned. “The mailbox.” 

The mailbox 12-year-old Dipper had discovered an odd decade ago sat in the same location. It still had moss on it, and the red flag was down, waiting for mail to answer. Mabel giggled and walked over to it, opening the lid of its mouth. 

“You got any paper, or pens, bro-bro? We could send it a letter again!” Mabel asked excitedly. Dipper chuckled warmly, pulling out his new sketchbook he’d gotten a couple of days ago. He was secretly glad he’d bought it with him. He walked over, but before he let Mabel take hold of it, he yanked it away. 

“Don’t do anything outrageous like the gummy-worm video, alright?” The male deadpanned passively as hi twin sister nodded. “I won’t...this time. Do you want to write the letter or should I?” 

Dipper shrugged carelessly. “Eh, do whatever. No harm done, right?” It wasn’t something he usually said, but the worst that ever happened with a maybe-future-telling mailbox was it magically exploding. 

He handed his twin siste a pen and she scribbled something down. He leaned over his shoulder. 

 

_Do you know who we are?_

 

Dipper huffed. “That’s kind of a stupid question, y’know.” Mabel scoffed, shoving the freshly-torn paper into the wide, gaping slot and closed the mailbox. “You’re the one who said ‘no harm done’. Don’t blame me!” As she spoke, the rusted mailbox began to shudder and rattle, making the Mystery Twins nerves twist in nervousness. 

The flag groaned as it lifted itself upright.

Mabel reopened the lid and pulled out a neatly-ribbon-tied scroll in replacement of Dipper’s sketchbook paper. She undid the ribbon and unrolled the tainted scroll. 

 

_You are Mason and Mabel Pines, grandniece and grandnephew of Stanford and Stanley Pines._

 

“Okay, the mailbox used my first name. That’s a little concerning.” Dipper whispered mostly to himself. He was getting that sense of dread, kind of like the feeling he felt when he suspected “Norman” to be a zombie (when he was actually a band of gnomes). 

“This thing knows everything!” Mabel exclaimed cheerily. She dug into Dipper backpack and pulled out his sketchbook, much to the other’s defiance. “Hey! Give that back; it’s mine!” 

Mabel tore out another piece, a lot less gracefully that her twin brother had done so, and scrawled something else down. Before Dipper could properly read it, she shoved it inside the mailbox and slammed the lid closed. 

After a few moments, the flag was upright again. 

_Mabel Pines’ secret crush: Pacifica Northwest._

 

Dipper watched as Mabel’s face contorted into into a pale shock. “Why’d you ask that? Couldn’t handle the confusion of love?” Mabel slapped him as he laughed. “Shut up, Dipshit!” She scolded, her face a deep red. 

Mabel crossed her arms, trying (and hilariously failing) to hide her true emotions. “How was I supposed to know? For all we know, you could have a crush on a guy!” She snapped her jaw shut as a devilish idea popped up in her head. Dipper looked at her in terror. 

“Mabel,” he warned, “don’t you dare!” 

Using the tatic of emojis and texting format, Mabel had already written her question and sent it to the mailbox. Dipper watched in anxiousness as the said item shuddered and rattled once again, and as Mabel smirked at him the whole entire time.

The girl opened the mailbox.

Dipper gulped. He didn’t have any crushes, let alone on a GUY, so he was dreading the answer. “Pleas say no, please say no...” he muttered to himself as Mabel unfolded the now-untied scroll. 

 

_Dipper Pines’ secret crush: ..._

 

Mabel grinned as she mouthed the words of her twin brother’s secret crush. 

 

Dipper watched her with wide eyes, having no idea what the scroll had revealed. 

 

Mabel inhaled slowly. Dipper whined pathetically, silently asking her to just spit it out. He wasn’t going to try and snatch it away from her; thatd make the reveal even worse. “JUST TELL ME ALREADY!” He shouted suddenly, startling himself but not Mabel. 

“Bill Cipher.” Mabel uttered almost immediately.

Dipper froze. Had he heard her right? This is not good at all. He let his hands fall to his sides. 

“Say that again.” He demanded quietly.

 

_Dipper Pines’ secret crush: Bill Cipher._

 

All the air left his lungs. His mouth felt very dry. He couldn’t swallow. A slow blush trickled onto his cheeks.

Mabel smirked even wider. “Looks like Dippy’s fallen for a demon!” She chanted mockingly as she crumpled up the scroll. He rushed over to his sister, grabbing his sketchbook out of her hands.

“Gimme the pen,” he ordered darkly, whilst Mabel obliged immediately, suddenly very worried. He wrote his own question down and sent it to the mailbox. 

 

_Will Bill Cipher return?_

 

A rattle there. A creak here. Then silence. 

 

_He already has. He has eyes everywhere._

 

Dipper looked around frantically, expecting a yellow triangle to show up out of the blue, cackling mercilessly. Mabel was given the letter ithout a word and she knew the answer. “Dip...” 

“SHUSH! He could be anywhere!” 

Mabel shut up after that. Her hiking trip with her twin brother didn’t end up so great like she thought it would. She just wanted quality time with Dipstick, but now he was looking for his supposed ‘secret crush’ in a frenzied panic. 

Why was he panicked in the first place? She tried again. “Bro...”

 

A twig broke nearby. 

 

A hurried scuttle from somewhere else. 

 

Mabel was blinded suddenly by a gloved hand, but before she could make a sound, her attacker sealed her lips with an actual zipper and key. “Don’t make a sound,” the stranger whispered, catching Dipper’s attention. 

Mabel gulped wordlessly. She heard Dipper turn around. 

“B-Bill?” The male brunette asked in a hushed voice. 

“In the flesh, Pine Tree.” He said, smiling.

The man who sealed Mabel’s lips wore a yellow tailcoat vest with a brick pattern at the hem. Black gloves hid his light-tanned hands, but not his handsome face. He donned floating top hat, an eyepatch on the right, and a white, half-sleeved dress shirt. His pants were as black as his gold-highlighted hair, and a cane in the same color was held over Mabel’s torso, a safe distance away from her chest. 

The humanized demon guestered to the molded, dented mailbox beside him. “Looks like you’re messing with lack of reality again, Pines. What brings you here?” He paused. “Oh, wait. I’m demon; I don’t need to ask that!” He boasted loudly. 

Dipper closed his eyes for a brief moment,

“Please let go of Mabel.”

Bill titled his head a little. “Why? She’d be a good puppet.” 

Dipper fiddled with his thumbs, thinking about the mailbox’s statement about his ‘secret crush’. “Just let her go.” He repeated just as quietly. 

Unnerved by the male’s passiveness, he silently uncovered the female’s eyes, unzipped her lips, and removed the cane from her personal boundaries. She turned around and gasped as she backed up towards her twin brother. 

“Is that...” she couldn’t finish her sentence. She was in too much shock. Dipper’s nod was all it took for an answer. 

There was an awkward silence before Bill (obviously somewhat human now) broke it.

“I hate to ask this, but my human emotions are getting in the way, but...why are you so quiet, Pine Tree?” Dipper flinched slightly. He kept his head bowed so the peak of his old hat hid his beet red face. 

“Mabel asked a personal question and I got a strange answer from the mailbox.” He replied, pointing to the same dented item next to the humanized demon. Mabel was a tad bit perplexed at why Dipper was in offense instead of defense, but of course his self-hidden feelings had to take the blame. 

Bill leaned down and pick up the discarded paper with the answer to Mabel’s unknowningly life-changing question.  “‘Dipper Pines’...” he read aloud, causing Dipper to shrink back just slightly. 

“‘...secret crush...’” he stopped reading. His golden eye flicked to Dipper’s hidden frame.

 

...

 

“‘Bill Cipher.’” 


End file.
